xref: /OK3568_Linux_fs/kernel/tools/arch/arm64/include/asm/barrier.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
3*4882a593Smuzhiyun #define _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun /*
6*4882a593Smuzhiyun  * From tools/perf/perf-sys.h, last modified in:
7*4882a593Smuzhiyun  * f428ebd184c82a7914b2aa7e9f868918aaf7ea78 perf tools: Fix AAAAARGH64 memory barriers
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * XXX: arch/arm64/include/asm/barrier.h in the kernel sources use dsb, is this
10*4882a593Smuzhiyun  * a case like for arm32 where we do things differently in userspace?
11*4882a593Smuzhiyun  */
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define mb()		asm volatile("dmb ish" ::: "memory")
14*4882a593Smuzhiyun #define wmb()		asm volatile("dmb ishst" ::: "memory")
15*4882a593Smuzhiyun #define rmb()		asm volatile("dmb ishld" ::: "memory")
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun /*
18*4882a593Smuzhiyun  * Kernel uses dmb variants on arm64 for smp_*() barriers. Pretty much the same
19*4882a593Smuzhiyun  * implementation as above mb()/wmb()/rmb(), though for the latter kernel uses
20*4882a593Smuzhiyun  * dsb. In any case, should above mb()/wmb()/rmb() change, make sure the below
21*4882a593Smuzhiyun  * smp_*() don't.
22*4882a593Smuzhiyun  */
23*4882a593Smuzhiyun #define smp_mb()	asm volatile("dmb ish" ::: "memory")
24*4882a593Smuzhiyun #define smp_wmb()	asm volatile("dmb ishst" ::: "memory")
25*4882a593Smuzhiyun #define smp_rmb()	asm volatile("dmb ishld" ::: "memory")
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun #define smp_store_release(p, v)						\
28*4882a593Smuzhiyun do {									\
29*4882a593Smuzhiyun 	union { typeof(*p) __val; char __c[1]; } __u =			\
30*4882a593Smuzhiyun 		{ .__val = (v) }; 					\
31*4882a593Smuzhiyun 									\
32*4882a593Smuzhiyun 	switch (sizeof(*p)) {						\
33*4882a593Smuzhiyun 	case 1:								\
34*4882a593Smuzhiyun 		asm volatile ("stlrb %w1, %0"				\
35*4882a593Smuzhiyun 				: "=Q" (*p)				\
36*4882a593Smuzhiyun 				: "r" (*(__u8_alias_t *)__u.__c)	\
37*4882a593Smuzhiyun 				: "memory");				\
38*4882a593Smuzhiyun 		break;							\
39*4882a593Smuzhiyun 	case 2:								\
40*4882a593Smuzhiyun 		asm volatile ("stlrh %w1, %0"				\
41*4882a593Smuzhiyun 				: "=Q" (*p)				\
42*4882a593Smuzhiyun 				: "r" (*(__u16_alias_t *)__u.__c)	\
43*4882a593Smuzhiyun 				: "memory");				\
44*4882a593Smuzhiyun 		break;							\
45*4882a593Smuzhiyun 	case 4:								\
46*4882a593Smuzhiyun 		asm volatile ("stlr %w1, %0"				\
47*4882a593Smuzhiyun 				: "=Q" (*p)				\
48*4882a593Smuzhiyun 				: "r" (*(__u32_alias_t *)__u.__c)	\
49*4882a593Smuzhiyun 				: "memory");				\
50*4882a593Smuzhiyun 		break;							\
51*4882a593Smuzhiyun 	case 8:								\
52*4882a593Smuzhiyun 		asm volatile ("stlr %1, %0"				\
53*4882a593Smuzhiyun 				: "=Q" (*p)				\
54*4882a593Smuzhiyun 				: "r" (*(__u64_alias_t *)__u.__c)	\
55*4882a593Smuzhiyun 				: "memory");				\
56*4882a593Smuzhiyun 		break;							\
57*4882a593Smuzhiyun 	default:							\
58*4882a593Smuzhiyun 		/* Only to shut up gcc ... */				\
59*4882a593Smuzhiyun 		mb();							\
60*4882a593Smuzhiyun 		break;							\
61*4882a593Smuzhiyun 	}								\
62*4882a593Smuzhiyun } while (0)
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun #define smp_load_acquire(p)						\
65*4882a593Smuzhiyun ({									\
66*4882a593Smuzhiyun 	union { typeof(*p) __val; char __c[1]; } __u =			\
67*4882a593Smuzhiyun 		{ .__c = { 0 } };					\
68*4882a593Smuzhiyun 									\
69*4882a593Smuzhiyun 	switch (sizeof(*p)) {						\
70*4882a593Smuzhiyun 	case 1:								\
71*4882a593Smuzhiyun 		asm volatile ("ldarb %w0, %1"				\
72*4882a593Smuzhiyun 			: "=r" (*(__u8_alias_t *)__u.__c)		\
73*4882a593Smuzhiyun 			: "Q" (*p) : "memory");				\
74*4882a593Smuzhiyun 		break;							\
75*4882a593Smuzhiyun 	case 2:								\
76*4882a593Smuzhiyun 		asm volatile ("ldarh %w0, %1"				\
77*4882a593Smuzhiyun 			: "=r" (*(__u16_alias_t *)__u.__c)		\
78*4882a593Smuzhiyun 			: "Q" (*p) : "memory");				\
79*4882a593Smuzhiyun 		break;							\
80*4882a593Smuzhiyun 	case 4:								\
81*4882a593Smuzhiyun 		asm volatile ("ldar %w0, %1"				\
82*4882a593Smuzhiyun 			: "=r" (*(__u32_alias_t *)__u.__c)		\
83*4882a593Smuzhiyun 			: "Q" (*p) : "memory");				\
84*4882a593Smuzhiyun 		break;							\
85*4882a593Smuzhiyun 	case 8:								\
86*4882a593Smuzhiyun 		asm volatile ("ldar %0, %1"				\
87*4882a593Smuzhiyun 			: "=r" (*(__u64_alias_t *)__u.__c)		\
88*4882a593Smuzhiyun 			: "Q" (*p) : "memory");				\
89*4882a593Smuzhiyun 		break;							\
90*4882a593Smuzhiyun 	default:							\
91*4882a593Smuzhiyun 		/* Only to shut up gcc ... */				\
92*4882a593Smuzhiyun 		mb();							\
93*4882a593Smuzhiyun 		break;							\
94*4882a593Smuzhiyun 	}								\
95*4882a593Smuzhiyun 	__u.__val;							\
96*4882a593Smuzhiyun })
97*4882a593Smuzhiyun 
98*4882a593Smuzhiyun #endif /* _TOOLS_LINUX_ASM_AARCH64_BARRIER_H */
99